--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtwamr/ec_gains.h	Mon May 06 02:08:43 2024 +0000
@@ -0,0 +1,147 @@
+/*
+********************************************************************************
+*
+*      GSM AMR-NB speech codec   R98   Version 7.6.0   December 12, 2001
+*                                R99   Version 3.3.0                
+*                                REL-4 Version 4.1.0                
+*
+********************************************************************************
+*
+*      File             : ec_gains.h
+*      Purpose:         : Error concealment for pitch and codebook gains
+*
+********************************************************************************
+*/
+#ifndef ec_gains_h
+#define ec_gains_h "$Id $"
+ 
+/*
+********************************************************************************
+*                         INCLUDE FILES
+********************************************************************************
+*/
+#include "typedef.h"
+#include "gc_pred.h"
+
+/*
+********************************************************************************
+*                         LOCAL VARIABLES AND TABLES
+********************************************************************************
+*/
+ 
+/*
+********************************************************************************
+*                         DEFINITION OF DATA TYPES
+********************************************************************************
+*/
+typedef struct {
+  Word16 pbuf[5];
+  Word16 past_gain_pit;
+  Word16 prev_gp;
+} ec_gain_pitchState;
+ 
+typedef struct {
+  Word16 gbuf[5];
+  Word16 past_gain_code;
+  Word16 prev_gc;
+} ec_gain_codeState;
+/*
+********************************************************************************
+*                         DECLARATION OF PROTOTYPES
+********************************************************************************
+*/
+
+/*
+**************************************************************************
+*
+*  Function    : ec_gain_code_reset
+*  Purpose     : Resets state memory
+*
+**************************************************************************
+*/
+void ec_gain_code_reset (
+    ec_gain_codeState *state
+);
+ 
+/*
+**************************************************************************
+*
+*  Function    : ec_gain_code
+*  Purpose     : conceal the codebook gain
+*                Call this function only in BFI (instead of normal gain
+*                decoding function)
+*
+**************************************************************************
+*/
+void ec_gain_code (
+    ec_gain_codeState *st,    /* i/o : State struct                     */
+    gc_predState *pred_state, /* i/o : MA predictor state               */
+    Word16 state,             /* i   : state of the state machine       */
+    Word16 *gain_code         /* o   : decoded innovation gain          */
+);
+
+/*
+**************************************************************************
+*
+*  Function    : ec_gain_code_update
+*  Purpose     : update the codebook gain concealment state;
+*                limit gain_code if the previous frame was bad
+*                Call this function always after decoding (or concealing)
+*                the gain
+*
+**************************************************************************
+*/
+void ec_gain_code_update (
+    ec_gain_codeState *st,    /* i/o : State struct                     */
+    Word16 bfi,               /* i   : flag: frame is bad               */
+    Word16 prev_bf,           /* i   : flag: previous frame was bad     */
+    Word16 *gain_code         /* i/o : decoded innovation gain          */
+);
+
+/*
+**************************************************************************
+*
+*  Function:   ec_gain_pitch_reset
+*  Purpose:    Resets state memory
+*
+**************************************************************************
+*/
+void ec_gain_pitch_reset (
+    ec_gain_pitchState *state
+);
+ 
+/*
+**************************************************************************
+*
+*  Function    : ec_gain_pitch
+*  Purpose     : conceal the pitch gain
+*                Call this function only in BFI (instead of normal gain
+*                decoding function)
+*
+**************************************************************************
+*/
+void ec_gain_pitch (
+    ec_gain_pitchState *st, /* i/o : state variables                   */
+    Word16 state,           /* i   : state of the state machine        */
+    Word16 *gain_pitch      /* o   : pitch gain (Q14)                  */
+);
+
+/*
+**************************************************************************
+*
+*  Function    : ec_gain_pitch_update
+*  Purpose     : update the pitch gain concealment state;
+*                limit gain_pitch if the previous frame was bad
+*                Call this function always after decoding (or concealing)
+*                the gain
+*
+**************************************************************************
+*/
+void ec_gain_pitch_update (
+    ec_gain_pitchState *st, /* i/o : state variables                   */
+    Word16 bfi,             /* i   : flag: frame is bad               */
+    Word16 prev_bf,         /* i   : flag: previous frame was bad     */
+    Word16 *gain_pitch      /* i/o : pitch gain                        */
+);
+ 
+#endif